the chemistry of climate change
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The Chemistry of Climate Change. The Science of Global Climate. - PowerPoint PPT PresentationTRANSCRIPT
The Chemistry of Climate Change
The Science of Global Climate
“There's a lot of differing data, but as far as I can gather, over the last hundred years the temperature on this planet has gone up 1.8 degrees. Am I the only one who finds that amazingly stable? I could go back to my hotel room tonight and futz with the thermostat for three to four hours. I could not detect that difference.”
-Dennis Miller
Climate
Climate is characterized by the statistical properties of the weather over a period of time, including averages of local variables such as temperature, winds, humidity, pressure, and precipitation.
June 12, 2001
Warming Threat Requires Action Now, Scientists Say
By ANDREW C. REVKIN
In his speech on climate yesterday, President Bush said that a basic problem with the Kyoto Protocol, the proposed international pact for curtailing global warming, was that it laid out a timetable for cutting releases of heat-trapping gases before the threat posed by a buildup of those gases was clearly understood.
New York Times
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Solar Radiation
Light scattering by gases
Light absorption by particles
Light scattering by particles
Light absorption by gases
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Solar Radiation
Solar Radiation
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Scattering and Absorption by Particulate Matter
‘modeled’
Solar Radiation
200 400 600 800
Wavelength (nm)
10-2
10-1
100
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Att
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Coe
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Aerosol Extinction
Ozone Absorption
RayleighScattering
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peak wavelength (nm)
Wein’s Law
Planck’s Relation
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Wavelength (nm)
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106
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3000 K
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Flux: number of photons per second per square centimeter
200 300 400 500 600 700
Wavelength (nm)
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Solar Radiation
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Solar Radiation
Radiative Power from Sun
Incident on Earth
Solar Flux
solar flux
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Solar Radiation
Global energy use by population ~ 1x1013 W
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Solar Radiation
Earth Emission
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Radiation Balance
Actual is 290 K
Calculated T/K Actual T/K
Earth 254 290 +36
Mars 217 223 +6
Venus 227 732 +505
Temperature at the Surface of Three planets: =Tactual-Tcalculated
Greenhouse Effect
300 nm
SpeciesAbsorption Region Estimated Global Warming
H2O 2.5, 3.5, 5-7 m ~110 Wm-2
CO2 14-19 m ~50 Wm-2
CH4 3-4, 7-8.5 m ~1.7 Wm-2
O3 9-10 m ~1.3 Wm-2
Greenhouse Gases